Leavenworth, Washington has a Humid Continental Climate - Dry Cool Summer climate (Köppen classification: Dsb). Average annual temperatures range from 38.1 °F (low) to 61.3 °F (high). Annual precipitation averages 20.9 Inches. Leavenworth is located in USDA Plant Hardiness Zone 7a. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 23.3 °F | 35.0 °F | 3.17 in. |
| February | 25.4 °F | 42.6 °F | 2.45 in. |
| March | 30.7 °F | 52.1 °F | 2.28 in. |
| April | 36.2 °F | 61.9 °F | 0.91 in. |
| May | 43.7 °F | 71.6 °F | 0.96 in. |
| June | 49.8 °F | 77.7 °F | 0.72 in. |
| July | 55.7 °F | 87.2 °F | 0.26 in. |
| August | 55.0 °F | 87.2 °F | 0.35 in. |
| September | 46.8 °F | 78.3 °F | 0.51 in. |
| October | 37.1 °F | 62.6 °F | 2.1 in. |
| November | 29.5 °F | 45.2 °F | 3.31 in. |
| December | 23.4 °F | 34.7 °F | 3.86 in. |
| Annual | 38.1 °F | 61.3 °F | 20.88 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 7a : 0°F to 5°F |
| Plant Hardiness Zone - 2012 | Zone 6b : -5°F to 0°F |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dsb - Humid Continental Climate - Dry Cool Summer |